code: def __str__(self):
      string = "Pipeline: "
      arrow = " -> "
      for transformer in self._transformers:
          string += str(transformer) + arrow
  
      return string[: -len(arrow)]
  
file_path: darts/darts/dataprocessing/pipeline.py
imports: from copy import deepcopy
  from typing import Iterator, Sequence, Union
  from darts import TimeSeries
  from darts.dataprocessing.transformers import BaseDataTransformer, FittableDataTransformer, InvertibleDataTransformer
  from darts.logging import get_logger, raise_if_not
label_desc: Use image node_id 12 for calling the Pipeline obj's underlying member method code with example usage: obj.__str__() and returns: string